Needled fabric and method of making the same



Oct. 28, 1941. H. A. REINHARDT 2,261,096

NEEDLED FABRIC AND METHOD OF MAKING THE SAME Filed March 29, 1937 INVENTOR Y HIMWY A 'RQmkM-AT ATTORNEY Patented Oct. 28, 1941 NEEDLED FABRIC AND METHOD OF MAKING THE SAME Henry A. Reinhardt, Amsterdam, N. Y., assignor to Bigelow-Sanford Carpet 00., Inc., Thompsonville,'Conn., a corporation of Massachusetts Application March 29, 1937, Serial No. 133,504

7 Claims.

My invention relates to improvements in the manufacture of needled or punched floor covering fabrics and more specifically to a rubberizing treatment applicable to such fabrics and to the product obtained thereby which I have found to possess superior wearing qualities.

In manufacturing needled or punched fabrics it has been suggested heretofore to apply to the back of the base fabric or other backing structure, after the needling or punching operation, some sort of binder such as an adhesive coating to secure the fibres to the base fabric. However, I have found that such external coating serves to bind only those portions of the needled fibres which have actually penetrated through the base fabric to be exposed to the coating material subsequently applied. The remaining fibres,

which have not sufiiciently penetrated the base fabric to be accessible to the adhesive, remain either unsecured adhesively, or only loosely secured, so that when the fabric is used the pile fibres soon scuff off.

It is an object of this invention to improve the wearing qualities of such fabrics by providing a better adhesive bind of substantially all of the fibres to the base fabric, regardless of their accessibility externally of the fabric, by effecting a complete penetration of the adhesive through the mass of fibres and into and through the base fabric.

It is a further object of this invention to provide novel adhesives for the purpose, as well as a novel method of impregnating the fabric with adhesive, which insure a superior product better adapted to withstand wear without sacrifice to texture, finish and flexibility, essential for marketability.

Artificial floor coverings of this type areusual- 1y printed with a colored design on their pile surfaces, and I have found that my method of employing adhesive, particularly with adhesives of the specific characteristics hereinafter set forth, does not in any way obscure the color or hinder the effectiveness of the printing operations.

Further objects and advantages of my invention will hereinafter be in part pointed out and l. The needling machine 5 operates to needle the fibres into the burlap, after which a second fibre layer 6 is usually deposited and. needled in by the machine 8.

The needled fabric I0 is then fed through a trough or tank I2 containing an adhesive material l3 preferably constituted as a vulcanizable latex dispersion of ingredients to be described. This trough has mounted therein suitable rollers properly positioned for completely immersing a continuously fed strip of the fabric l0. At the outlet end of the tank are mounted suitable squeeze rolls I4, which may be of rubber or other suitable material, and which are so mounted as to be easily adjusted in clearance to vary the pressure applied to the fabric I0, continuously fed therethrough. The pressure of the squeeze rolls serves not only to remove excess liquid, but also to effect a more complete penetration of the adhesive material into and through the backing structure for intimate contact with the fibres needled therethrough.

From the rolls I4 the fabric I0 is fed over a series of calenders l6 for calendering both sides of the fabric as indicated. The calenders are heated by steam or other means to a temperature of approximately 200 F. which act to aid the adhesive penetration, to remove some of the moisture and partly to vulcanize the rubber deposited. From the calenders the fabric is fed through a festoon dryer 20 to complete the vulcanization by exposure, for approximately two hours, to a temperature of approximately 220 F. to 240 F., obtained by the usual currents of hot air. The material may then be printed in the manner diagrammatically indicated, by feeding the material between an impression cylinder '20 and the usual printing rolls 2|, after which the web is passed through a steamer 22 and a dryer 24 to set the color.

The adhesive material used in the tank l2 may vary to suit the needs of individual manufacturers, but I have found that a dilute suspension of an unvulcanized but vulcanizable latex compound in water is desirable. If the rug is to be printed, as is customary, an adhesive which does not obscure such printing should be used. To that end any color which may be imparted to the rug by the adhesive should be of a light shade and of a tint approaching the natural color of the jute or other fibres themselves, which I shall hereinafter refer to as a neutral shade. Hevea brasiliensis or crude latex containing approximately 40% dry solids and 60% water by weight produce a neutral shade adhesive and contain' Crude latex (60% water) 100.00 Zinc oxide 0.81 Zinc salt of dibutyldithiocarbamate 0.40 Symmetrical di beta naphthyl paraphenylene diamine 0.40 Sulfur flour -z 0.51 Sulfonated aromatic compound such as "Darvan 0.08 Casein 0.06 Ammonium hydroxide 0.01 Sodium hydroxide 0.04

As a second phase in the adhesive preparation, karaya gum, sodium carbonate and water are mixed with each other in substantially the following amounts relative to the above:-

Parts by weight Karaya gum 0.28 Sodium carbonate 0.22 Water 18.87

After the foregoing mixtures have been separately obtained, the two mixtures are combined with each other and a still further quantity of water added to dilute the mixture and thereby enhance its penetrating properties. There may also be added at this time a small amount of a wetting or penetrating agent such as a sulphonated aliphatic alcohol, obtainable in the trade as Igepon.

The quantityof water added should be suflicient to form an aqueous suspension of latex mix having approximately between 5% and and preferably 7% solids by weight and the amount of Igepon added at this time may approximate .4% of the total weight of the mixture.

In the passage of the fabric through the squeeze rolls I4, I preferably apply sufiicient pressure to reduce the water content about 50%. After calendering and complete drying, a fabric which, after needling weighs 25 lbs. should increase approximately 3 lbs. in weight by the solids deposited. My experiments have indicated that for optimum adhesion without sacrifice to flexibility, the solids deposited should not vary more than .2 lb. from that figure of 3 lbs. solids per rug weighing 25 lbs. after needling.

I have found that the above mixture is very efiective as an adhesive binder and it ages well. It does not become tacky or odoriferous on exposure to heat, nor hard or brittle on exposure to cold temperatures. As stated above, the printing operations are in no way deleteriously affected by the adhesive deposited on the fibres. My experiments have indicated that as a result of the high dilution of the rubber dispersion, the adhesive tends to coalesce into droplets which accumulate chiefly at the intersections of the fibres where adhesion is desired. However, even insofar as the fibres themselves may be coated, the

rubber material readily takes acid dyes and the neutral shade of the rubber is conducive to good printing results.

The ingredients, however, may be varied, such as by the substitution of white, water-dispersed reclaimed rubber for the latex. A prevulcanized latex also can be used, if desired.

The method of applying the adhesive also may be varied if desired. Thus, I have also prepared my fabric by spraying, but the penetration results, while successful, are not as complete as in the bath treatment.

I claim:

1. The method of binding the fibers of .a needled felt fabric without the formation of a continuous surface coating on the fabric which consists in thoroughly wetting the needled fabric with a very thin aqueous dispersion of rubber adhesive containing not more than approximately 15% solids by weight, squeezing the fabric to cause the bath to permeate through the fabric while removing from the fabric a large portion of the diluent and subsequently treating the fabric to set the adhesive thereby deposited so that the needled fibers of the fabric are adhered together by accumulations of adhesive at the fiber intersections without materially stiifening the fabric.

2. The method of binding the fibers of a needled felt fabric without the formation of a continuous surface coating on the fabric which consists in thoroughly wetting the needled fabric with a very thin aqueous dispersion of rubber adhesive containing between approximately 5% and 15% solids by weight, squeezing the fabric to cause the bath to permeate through the fabric while removing from the fabric a large portion of the diluent and subsequently treating the fabric to set the adhesive thereby deposited so that the needled fibers of the fabric are adhered together by accumulations of adhesive at the fiber intersections without materially stiffening the fabric.

3. The method of binding the fibers of a needled felt fabric without the formation of a continuous surface coating on the fabric which consists in immersing the fabric in a very thin aqueous dispersion of rubber adhesive containing between approximately 5% and 15% solids by weight, squeezing the fabric after removing it from the bath to cause the bath to permeate uniformly through the fabric and to remove a large portion of the diluent and subsequently treating the fabric to set the adhesive so that the needled fibers are adhered together by accumulations of the adhesive at the fiber intersections without materially stiffening the fabric and leaving portions of the fibers free of adhesive to take printing dies.

4. The method of binding the fibers of a needled felt fabric without the formation of a continuous surface coating on the fabric which consists in thoroughly wetting the fabric with an aqueous dispersion of rubber containing Vulcanizing agents and having not more than 15% solids by-weight, squeezing the fabric to cause the adhesive bath to permeate uniformly through intersections withoutv materially stiflening the fabric.

5. An uncoated needled felt fabric composed of fibers punched through a backing fabric and impregnated with a rubber adhesive composition which is distributed throughout the fabric from top to bottom, the said adhesive being present chiefly as accumulations at the fiber intersections to secure the top fiber against scufllng out without materially stiffening the fabric.

6. The method of binding the fibers of a needled felt fabric without the formation of a surface coating on the fabric which consists in thoroughly wetting the needled fabric with a very thin aqueous dispersion of rubber adhesive containing between approximately 5% and 15% solids by weight, squeezing'the fabric to cause the bath to permeate through the fabric while removing from the fabric a large portion of the diluent and subsequently treating the fabric to set the adhesive thereby deposited so that .the

needled fibers of the fabric are adhered together by accumulations of adhesive at the fiber intersections without materially stiifening the fabric and so that the weight of the untreated needled fabric is increased by the adhesive in an amount approximating 3 pounds adhesive solids per 25 pounds of untreated fabric.

7. A needled felt fabric composed of fibers punched through a backing fabric and impregnated with a rubber adhesive composition which is distributed throughout the fabric from top to bottom, the said adhesive being present chiefly HENRY A. REINHARDT. 

